SZT2 指令GATOR控制mTORC1的信号
Min Peng1, Na Yin1, Ming O Li1
1Immunology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA.
Nature
|February 16, 2017
概括
抓获值2 (SZT2) 蛋白与GATOR1和GATOR2形成复合体,这对于通过mTORC1信号传递来感知和控制细胞生长至关重要. SZT2 缺乏破坏了这一过程,导致小鼠细胞功能障碍和新生儿死亡.
科学领域:
- 细胞生物学
- 营养感应的分子机制
- 信号传输路径
背景情况:
- 通过整合营养信号来调节细胞生长和平衡.
- 包括GATOR1和GATOR2在内的GATOR复合体通过Rag GTPases调节mTORC1的信号传递.
- 甲状腺特异性SESN蛋白与GATOR2相互作用,但它们在mTORC1调节中的作用尚不清楚.
研究的目的:
- 调查SZT2 (抓获值2) 在营养感应和mTORC1调节中的功能.
- 阐明SZT2,GATOR复合体和SESN蛋白之间的相互作用.
- 了解SZT2编排的GATOR (SOG) 综合体在细胞平衡中的作用.
主要方法:
- 生物化学测试以描述SOG复合物的形成和相互作用.
- 使用显微镜进行细胞定位研究.
- 在各种营养条件下分析SZT2缺乏细胞和小鼠的mTORC1信号.
- 基因操纵 (过度表达) 来挽救mTORC1的过度激活.
主要成果:
- SZT2 与 GATOR1 和 GATOR2 形成了一个新型的 SZT2 编排的 GATOR (SOG) 复合体,这对 lysosomal 定位至关重要.
- 由于禁食期间mTORC1受损,SZT2缺乏导致营养缺乏和新生儿死亡的mTORC1信号.
- 过度表达DEPDC5 (GATOR1) 或化体向的WDR59 (GATOR2) 或SESN2在SZT2缺乏细胞中部分纠正mTORC1过度活化.
结论:
- 通过促进SOG复合体的溶解体局部化,SZT2在营养感应中发挥着关键作用.
- 通过SESN招募, lysosome局部化的GATOR2意外地抑制了mTORC1的信号传递.
- SOG复合体对于维持生物体的平衡和防止mTORC1过度激活至关重要.
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